what could I do to get my trx 250 up to around 50 mph? also if I got a motor and swing arm from a 300 or 400ex would they fit on my 250 frame? thanks p.s yeah I know you guys probably think I'm stupid.

 

The only way to increase top speed is to go to larger rear tires since the machine is shaft driven and cannot be regeared. Unfortunately, this will cost you acceleration, which is a lousy trade, in my opinion.

 

why doesn't honda or somebody in the aftermarket make optional rear end gear sets the you can buy to regear the quad if you want?

 

The 300 and 400 are chain drive not shaft, so just forget that idea.

Have you already done the basic mods like air intake, exhaust, and a rejet???

We had the stock 22" tires on for a while recently, and I found them very lame in terms of acceleration compared to the 20" tires we had been running.

 

yes I have done the k&n filter the new exhaust and rejetted the carb. I mostly trail ride which make the small size of the 250 good but I would like to have a bit more top speed out of it. which is why I wish that somebody made optional rear end gears for the 250. yesterday I though about buying a new quad but after sleeping on it I just don;t think that I want to spend the 8,100 that my local dealer wants for the 700xx that I was looking at. so I guess I will have to keep my slow little turd a while longer.

 

On my local very tight mountain woods trails, the little 250 rocks! Not much more you can do to get more top end, without doing stupid things to the engine. I always like a torquey bottom end, so I go with the 20" rear tires.

 

thanks reconranger, i think that I might keep the little 250 around for a while at least until I get it payed off, I was thinking about trying out a rev box on the little guy to see if it would let me be able to pull the gears longer? by the way do you know of anybody thta makes a bigger oil cooler that I could put on my 250ex? thanks.

 

i have a 2007 trx250ex i have some mods---HMF full exhaust system,,,dyno jet kit,,,K&N air filter,,,Vapor speedometer and i also have a crf caborater --- i havent been able to top out but but i have done little tests---1st gear i can go 20mph at around 8700 rpm,,,2nd gear 30mph 8700rpm,,,3rd gear 40mph 8700rpm,,,4th gear 49.7mph 8700 and i didnt have enough room in that small parking lot to do 5th gear but i would say i could hit 58-60mph at top rpm which is limited at 8750,,,i have gone 53.6 in the parking lot though at 7400rpm so i hope this helps you! the quad is just to small for me and way to slow for me!!! i am 15 but im very experienced with anything with an engine and i even drive tractor trailers --- so i should be getting a 450 this august --- i really really really want a yfz450r but i like reverse and i do alot of trail riding so i might be going with a kfx450r --- have fun with your 250